Description of Osteochondritis Dissecans Knee
Osteochondritis dissecans can affect any joint in the body but the knee is the most commonly affected joint.
Osteochondritis dissecans of the knee, or OCD knee, is a condition that is caused by a reduction of blood flow to the end of a bone within the knee joint. This condition occurs most often in adolescent males under the age of 25. OCD of the knee is a painful joint condition in which a piece of cartilage, along with a portion of the bone under it, may come loose from the end of a bone.
Some individuals who have this condition may or may not experience symptoms. One of the most important prognostic factors for OCD is whether the patient’s growth plates are still open. If the loosened cartilage and bone does not completely detach, with rest and limited activity, the fragment has the ability to naturally repair itself if their growth plates are still open. In patients whose growth plates are closed or where the bone has completely detached, symptoms will often be present and could continue to get worse.
Symptoms associated with osteochondritis dissecans knee include:
- Swelling: The area around the knee joint will become swollen and tender
- Pain: Pain is the most evident symptom of this condition; it will continue to worsen with activity.
- Limited Range of Motion: As the condition worsens, it will become more difficult to straighten your leg
- Joint Locking: When the bone and cartilage detach from the end of a bone in the knee joint, loose fragments are at risk for getting caught between the bones. This may result in the joint locking up, popping or getting stuck (locked) in one position. Sometimes patients can feel fragments floating in their joints, usually up and around the kneecap.
Young athletes appear to be at risk for developing OCD of the knee. Sports that involve quick moves and fast changes in direction may increase the chances. Ongoing over-use, knee trauma, repetitive, unrecognized injuries and other episodes or hard falls could also damage the end of an affected bone.
How to Read a MRI of an Osteochondritis Dissecans Lesion
Treatment of Osteochondritis Dissecans Knee
Dr. LaPrade offers specialized treatment for osteochondritis dissecans of the knee. In order to properly diagnose this condition and plan the most affective course of treatment, he will order specific x-rays and usually an MRI. X-rays will be needed so that Dr. LaPrade can determine if the patient is bow-legged or knock-kneed and to determine the location of the defect. X-rays also help to visually the opposite knee, which is important because 30% of patients will have OCD in both knees. The MRI will offer him the ability to examine the extent of the injury through detailed imaging of the joint to determine the defect size, whether it is one piece or fragmented, and to evaluate for the presence of cysts in the surrounding bone. Treatment for osteochondritis dissecans of the knee will vary depending on the patient. If the MRI shows that the cartilage and bone have not completely detached in a patient with open growth plates, Dr. LaPrade will first establish a protocol involving rest, the use of crutches, range of motion exercises, strengthening moves, and possibly anti-inflammatory medication. These are conservative measures for the treatment of OCD knee that are taken for the affected joint to restore normal function.
In patients where Dr. LaPrade recommends surgery, an arthroscopic surgical approach may be performed to drill into the dead bone or to remove the loose fragments and debris deep in the lesion in the knee joint and reattach the bone with bioabsorbable screws and bone graft. Dr. LaPrade may use a fresh donor cartilage allograft in patients with a large and/or deep lesion, in which case the patient will need a second surgery and be put on a cartilage donor list. In these circumstances, a cartilage allograft is used to replace the bone and cartilage that has fallen off.
A very specific, detailed post-op protocol will be given to patients who undergo arthroscopic surgery for the treatment of osteochondritis dissecans. It is crucial that the patient work directly with rehab specialists and Dr. LaPrade in following this precise treatment plan. Patients who have a drilling procedure or a reattachment of their defect with bone grafting will be advised to avoid putting weight on their foot for a minimum of 6 weeks and may need to use an unloader brace for a few months after surgery. For those who undergo a fresh osteoarticular allograft procedure, they will be non-weight bearing for 8 weeks and will need to use a CPM for 6-8 hours a day while they are non-weight bearing. Depending on the severity of the injury and surgical repair site and size, some patients will be told to modify their current activities (partaking in competitive or recreational sports). This is often the case when a cartilage transplant takes place.
- Refrigerated Osteoarticular Allografts
- Articular Cartilage Injuries of the Knee